Hiyori Kazane

Hiyori Kazane (風音　日和) is a second-year student at Tomoki's school. In reality, Hiyori is an Angel who was first seen inside some sort of sleeping chamber, which allows them (Angels) to dream, when Sugata went to Synapse. The chamber connects her to her body on Earth, which functions like an avatar. She has feelings for Tomoki and joins the New World Discovery Club to get closer to him.

Personality
Hiyori is kind and shy. She loves to grow crops. Whenever Tomoki walks by when she's farming, she hides because she is embarrassed Tomoki will see her dirty.

In her Angeloid from, she is still the same. In the movie, the Man of Synapse brainwashes and controls Zeta. When being controlled, she is silent, robotic and only uses her abilities to kill Tomoki and his friends. She regains her personality and memories after Tomoki returns her bell ornament.

In the manga series, Hiyori expressed a more brazen and sometimes flirtatious side of herself only known to Tomoki. For example, when Hiyori kissed Tomoki under the tree, she explained how even though she knew he didn't return her romantic feelings, she was still going to try to win Tomoki's heart.

Another example of her newly developed flirtatious persona is when Tomoki ran around the school with Sohara Mitsuki pursuing him, asking girls if they "Loved Him" while touching their breasts. After several rejections, Tomoki came upon Hiyori and asked her if he can "grope her". She agreed to his request only if he agreed to "Go out with her".

Appearance
Hiyori is a beautiful young girl with black hair tied into a ponytail on her upper back and blue eyes, she also has two pairs of white angel wings that were altered when turned into an Angeloid.

She is initially seen in her farmer's clothes. She wears the regular uniform of Sorami School while attending classes. As a regular angel, she wears a yellow dress with an orange lining. After being converted into an Angeloid, she sports a choker with a chain. She possesses wings like all other Angeloid. She carries a staff with her after becoming an angeloid.

Her most noble feature is her hair tie on the left side of her hair with two bells.

Hiyori Kazane
Her first appears in the 5th episode of the second season of the anime, but has a limited role. She is not actually introduced in the anime at that time but it is foreshadowed that she will be a significant and important character in the future. Hiyori is the central character of the movie Sora no Otoshimono the Movie: The Angeloid of Clockwork. She initially appears to be a human before being revealed as an inhabitant of synapse. She dies in a traffic accident and wakes up in Synapse from her "dream". She is then willingly converted into an Angeloid by the Master of Synapse and sent to destroy Tomoki and the Angeloids on Earth.

She joins the club to get close to Tomoki despite never interacting with him before. Angeloids Nymph and Astraea harbor strong feelings for Tomoki and do not appreciate her getting involved.

Unknown to Tomoki, Sohara, and Mikako Satsukitane, Hiyori is not the simple 2nd-year student she appears to be. In one of his earlier trips to the mysterious world of Synapse (using one of Nymph's machines to access it via Tomoki's recurring dream), Eishiro Sugata ventured into a massive domed complex located on one of the many floating islands in Synapse to explore the world of the angels in depth. After searching around, he came across a gigantic room filled with thousands of metal capsules that each contain the bodies of slumbering angels, living out a "dream" on Earth as a way of keeping occupied in Synapse. While he was searching the room, he came across, to his horror and amazement, a capsule containing a winged version of Hiyori Kazane, sleeping peacefully as she muttered something related to Tomoki. Only Eishiro (along with all three of the Angeloids back on Earth) knows the truth behind Hiyori's past and who/what she really is.

She later shows up to join the New World Discovery Club. Tomoki, shocked that someone would be insane enough to actually join their club which gets involved in wild, crazed misadventures on a regular basis, decides to attempt to prevent her from joining the club. Over the next few days, he tried everything that he could think up a series of bizarre, perverted "purity" tests that he thought would prevent her from staying involved with the club to scare her away to the point that she would never come back, but she completes all of his tests and did not leave the club (much to Tomoki's bewilderment). His "tests" include Takoyaki Vendor's food, and several other embarrassing and perverted activities. He begins to harbor feelings for Hiyori, who seems to always ignores his faults and treats him kindly compared to Sohara and the Angeloids whenever he acts perverted in front of them.

Hiyori's Awakening
Tomoki is surprised when she confesses to him (no one, especially a girl, has ever taken such an interest in him before). He begins to fall in love with Hiyori, and dreams of the things that they can do together in the future. When he arrives to confess his feelings at the location they agreed on, he is horrified when a truck kills Hiyori. To his horror, she begins to dissolve away, and his memories of her existence begin to fade away (along with Sohara, Eishiro, and Mikako, who also lose all memory of her existence after she dies).

Eishiro, who is currently making another trip to Synapse to learn more about the inhabitants who call it home, suddenly begins to forget everything he knew about Hiyori as she dies back on Earth. With only several minutes before every memory of her disappears forever, Sugata charges past the twin Harpies (who are searching for him since he is trespassing there), and back into the dome, hoping to see her awake from her "dream" on Earth. To her amazement, Hiyori wakes up in her pod in Synapse, horrified that she has awakened from the dream and can never experience the same dream again. Seeing Eishiro before her brings tears to Hiyori, who knows that soon no one that she met back on Earth will ever remember her existence. She goes into a panic, and tries to re-dial the same dream, but is interrupted by the arrival of the mysterious Man of Synapse (along with the Harpies, his two Angeloid servants). He reminds her that she can never have the same exact dream again, and decides to let Eishiro go since he is entertained and Eishiro will soon forget everything in several moments.

Angeloid Hiyori
Hyori returns as a newly converted 2nd Generation Angeloid sent to eliminate Tomoki Sakurai, his fellow human friends, and wipe out Ikaros, Nymph, and Astraea. She was converted into a 2nd Generation Angeloid (Type Zeta) by the Man of Synapse, who promised her that she could "continue" to live her life out on Earth, wielding the powerful staff known as the "Demeter" (which grants her total control over time and space). Eventually, the Synapse tries to sap out the memories of Hiyori that Tomoki still has, but no one else does. Hiyori, on her way to attack the city of Sorami, is met by the three Angeloids and engages them in combat.

Nymph tries to hack into her systems but is met with a counterattack as the Man of Synapse reveals that he installed first-class electronic warfare equipment in Hyori. Tomoki manages to cool her down by returning her bells. Tomoki is surprised when he finds out of her return and decides to become friends with her once again, but Hiyori decides shortly afterwords to resign from The New World Discovery Club and sets off to enjoy her new freedom on Earth as a free Angeloid, as she achieved her goal of being closer to Tomoki. She makes a rare appearance in later chapters of the manga, most notably when she discovers the traumatized and injured form of Chaos that is laying on the dirt road and is crying next to her vegetable garden after taking massive damage when attempting to return back to Synapse (which her former master, the Man of Synapse, forbids and launches a massive shot of pure energy via the powerful Zeus Canon at her, damaging one of her wings in the process). Hiyori is last seen watching in complete shock as Chaos launches up into the air and rushes off into the distance, making a beeline towards where Tomoki's house is. In the chapters that follow, Hiyori is seen from time to time, usually shown tending to her vegetable patch or doing minor chores.

Several elements of her story were changed in the movie from the manga. She stays Zeta forever since she had lost her biological body. Around chapters 36-40, she has made her appearance. She doesn't die in the manga version, she just flies away and kisses Tomoki. The next day, she returns to school in her Zeta form.

Ikaros Melan Arc
Hiyori Kazane appears towards the end of the Ikaros Melan Arc. She is seen standing alongside Sohara and the others as Ikaros, Nymph, and Astraea struggle with the newest threat sent down from Synapse. Although she does not directly contribute to the fight, she visits Tomoki's house in her Angeloid gear in case that she is needed in the struggle against Ikaros Melan and the advanced Angeloids that the Man of Synapse has sent to kill Tomoki. In the aftermath of Ikaros Melan's defeat and the snapping of the Man of Synapse's sanity, Hiyori joins the others at the hospital to wish the battered Tomoki well as he tries to recover from the terrible injuries that he sustained at the hands of Ikaros Melan.

Abilities and Weapons
After being converted into a 2nd Generation Angeloid by Minos to use against Tomoki and the other Angeloids down on Earth, Hiyori gains the power of flight, superhuman speed, and the ability to control and bend the elements around her to her will, made possible with the aid of her powerful Demeter staff.

She tries to kill Tomoki Sakurai by lowering the air pressure around Sorami to a dangerously low level, effectively putting the entire town at a high risk of death. As she lowered the pressure around them, Tomoki begins bleeding from his ears. In the anime, Hiyori was the power over time and possibly space.

Relationships

 * Tomoki Sakurai - Friend and love interest.


 * Sohara Mitsuki - Friend and love rival.


 * Eishirou Sugata - Friend.


 * Mikako Satsukitane - Friend.


 * Nymph - "Sister" and love rival.


 * Ikaros - "Sister" and love rival.


 * Master of Synapse - Former master and enemy.


 * Chaos -  "Sister" and Friend.


 * Astraea - "Sister" and love rival.


 * Oregano - "Sister" and Friend.

Trivia

 * Her name sounds like Shiori Kazami, the name of Shun Kazami's mother (from Bakugan Battle Brawlers).
 * Her weapon "Demeter" is named after the Greek goddess of agriculture and crops (Δήμητρα).
 * Kayros might be a reference to the Greek word for weather (καιρός), which in some occasions means time. She has control over both. She can manipulate the weather in the manga and space-time in the anime. Both times, Demeter allows her access to it.
 * She is deceased as of manga chapter 70. Chaos at first sought to eat her against Hiyori's will, but after Hiyori beheld a "flow of memories" from Chaos, showing the level of moral damage inflicted by Chaos's creator Minos, Hiyori realized that Chaos needed someone to set her moral compass straight. She then willingly impaled herself onto Chaos's wingtip, giving Chaos all her powers and knowledge, including a strong sense of morality. However, in Chapter 77 she was revived along with everybody else.
 * Hiyori narrates in the first movie.
 * In the 2014 movie Sora no Otoshimono: Eternal my master, Hiyori is one of the main characters.
 * In the first movie Hiyori has black hair, but in the second movie trailer she is shown having navy blue hair like the manga.
 * In the first movie, Hiyori met Tomoki when they were children at their favorite place. At the end of the movie, she meets him there again after apparently dying.
 * Hiyori's appearance & death is similar to Xion from Kingdom Hearts 358/2 Days.
 * She has a dress similar to Maori from Arcana Hearts.